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Top > Service Director > Domain Manager > Name Servers > New Name Server

Remember that domain's DNS zone is synchronized with SSH-manageable Name Servers only. Actually:

Non-manageable name server. If you want to register a third-party name server that answers the Parallels Business Automation - Standard DNS requests, but does not support automated zone files synchronization. For example, you can use this type of registration for your secondary name server.

Name server to be managed over SSH. If you want to register the physical name server and if you want changes made to a domain (e.g., if more hostnames were added) to be automatically synchronized with appropriate zone files on this name server.
There are 2 different tasks for SSH-manageable Name Server - Registration and Synchronization:

When a domain with DNS Hosting is added to PBA-S, file named.zones is updated at slaves name servers and named is reloaded there. This makes the domain be resolved at the slave name servers. Refer to this KB article for troubleshooting of synchronization problems.